src/base.rs

   1 use rustc::ty::adjustment::PointerCast;
   2
   3 use crate::prelude::*;
   4
   5 pub fn trans_fn<'a, 'clif, 'tcx: 'a, B: Backend + 'static>(
   6     cx: &mut crate::CodegenCx<'clif, 'tcx, B>,
   7     instance: Instance<'tcx>,
   8     linkage: Linkage,
   9 ) {
  10     let tcx = cx.tcx;
  11
  12     let mir = tcx.instance_mir(instance.def);
  13
  14     // Declare function
  15     let (name, sig) = get_function_name_and_sig(tcx, instance, false);
  16     let func_id = cx.module.declare_function(&name, linkage, &sig).unwrap();
  17     let mut debug_context = cx
  18         .debug_context
  19         .as_mut()
  20         .map(|debug_context| FunctionDebugContext::new(tcx, debug_context, mir, &name, &sig));
  21
  22     // Make FunctionBuilder
  23     let mut func = Function::with_name_signature(ExternalName::user(0, 0), sig);
  24     let mut func_ctx = FunctionBuilderContext::new();
  25     let mut bcx = FunctionBuilder::new(&mut func, &mut func_ctx);
  26
  27     // Predefine ebb's
  28     let start_ebb = bcx.create_ebb();
  29     let mut ebb_map: HashMap<BasicBlock, Ebb> = HashMap::new();
  30     for (bb, _bb_data) in mir.basic_blocks().iter_enumerated() {
  31         ebb_map.insert(bb, bcx.create_ebb());
  32     }
  33
  34     // Make FunctionCx
  35     let pointer_type = cx.module.target_config().pointer_type();
  36     let clif_comments = crate::pretty_clif::CommentWriter::new(tcx, instance);
  37
  38     let mut fx = FunctionCx {
  39         tcx,
  40         module: cx.module,
  41         pointer_type,
  42
  43         instance,
  44         mir,
  45
  46         bcx,
  47         ebb_map,
  48         local_map: HashMap::new(),
  49
  50         clif_comments,
  51         constants: &mut cx.ccx,
  52         caches: &mut cx.caches,
  53         source_info_set: indexmap::IndexSet::new(),
  54     };
  55
  56     with_unimpl_span(fx.mir.span, || {
  57         crate::abi::codegen_fn_prelude(&mut fx, start_ebb);
  58         codegen_fn_content(&mut fx);
  59     });
  60
  61     // Recover all necessary data from fx, before accessing func will prevent future access to it.
  62     let instance = fx.instance;
  63     let clif_comments = fx.clif_comments;
  64     let source_info_set = fx.source_info_set;
  65
  66     #[cfg(debug_assertions)]
  67     crate::pretty_clif::write_clif_file(cx.tcx, "unopt", instance, &func, &clif_comments, None);
  68
  69     // Verify function
  70     verify_func(tcx, &clif_comments, &func);
  71
  72     // Define function
  73     let context = &mut cx.caches.context;
  74     context.func = func;
  75     cx.module
  76         .define_function(func_id, context)
  77         .unwrap();
  78
  79     let value_ranges = context.build_value_labels_ranges(cx.module.isa()).expect("value location ranges");
  80
  81     // Write optimized function to file for debugging
  82     #[cfg(debug_assertions)]
  83     crate::pretty_clif::write_clif_file(cx.tcx, "opt", instance, &context.func, &clif_comments, Some(&value_ranges));
  84
  85     // Define debuginfo for function
  86     let isa = cx.module.isa();
  87     debug_context
  88         .as_mut()
  89         .map(|x| x.define(tcx, context, isa, &source_info_set));
  90
  91     // Clear context to make it usable for the next function
  92     context.clear();
  93 }
  94
  95 fn verify_func(tcx: TyCtxt, writer: &crate::pretty_clif::CommentWriter, func: &Function) {
  96     let flags = settings::Flags::new(settings::builder());
  97     match ::cranelift::codegen::verify_function(&func, &flags) {
  98         Ok(_) => {}
  99         Err(err) => {
 100             tcx.sess.err(&format!("{:?}", err));
 101             let pretty_error = ::cranelift::codegen::print_errors::pretty_verifier_error(
 102                 &func,
 103                 None,
 104                 Some(Box::new(writer)),
 105                 err,
 106             );
 107             tcx.sess
 108                 .fatal(&format!("cranelift verify error:\n{}", pretty_error));
 109         }
 110     }
 111 }
 112
 113 fn codegen_fn_content<'a, 'tcx: 'a>(fx: &mut FunctionCx<'a, 'tcx, impl Backend>) {
 114     for (bb, bb_data) in fx.mir.basic_blocks().iter_enumerated() {
 115         if bb_data.is_cleanup {
 116             // Unwinding after panicking is not supported
 117             continue;
 118         }
 119
 120         let ebb = fx.get_ebb(bb);
 121         fx.bcx.switch_to_block(ebb);
 122
 123         fx.bcx.ins().nop();
 124         for stmt in &bb_data.statements {
 125             fx.set_debug_loc(stmt.source_info);
 126             trans_stmt(fx, ebb, stmt);
 127         }
 128
 129         #[cfg(debug_assertions)]
 130         {
 131             let mut terminator_head = "\n".to_string();
 132             bb_data
 133                 .terminator()
 134                 .kind
 135                 .fmt_head(&mut terminator_head)
 136                 .unwrap();
 137             let inst = fx.bcx.func.layout.last_inst(ebb).unwrap();
 138             fx.add_comment(inst, terminator_head);
 139         }
 140
 141         fx.set_debug_loc(bb_data.terminator().source_info);
 142
 143         match &bb_data.terminator().kind {
 144             TerminatorKind::Goto { target } => {
 145                 let ebb = fx.get_ebb(*target);
 146                 fx.bcx.ins().jump(ebb, &[]);
 147             }
 148             TerminatorKind::Return => {
 149                 crate::abi::codegen_return(fx);
 150             }
 151             TerminatorKind::Assert {
 152                 cond,
 153                 expected,
 154                 msg,
 155                 target,
 156                 cleanup: _,
 157             } => {
 158                 let cond = trans_operand(fx, cond).load_scalar(fx);
 159                 // TODO HACK brz/brnz for i8/i16 is not yet implemented
 160                 let cond = fx.bcx.ins().uextend(types::I32, cond);
 161                 let target = fx.get_ebb(*target);
 162                 if *expected {
 163                     fx.bcx.ins().brnz(cond, target, &[]);
 164                 } else {
 165                     fx.bcx.ins().brz(cond, target, &[]);
 166                 };
 167                 trap_panic(fx, format!("[panic] Assert {:?} failed at {:?}.", msg, bb_data.terminator().source_info.span));
 168             }
 169
 170             TerminatorKind::SwitchInt {
 171                 discr,
 172                 switch_ty: _,
 173                 values,
 174                 targets,
 175             } => {
 176                 let discr = trans_operand(fx, discr).load_scalar(fx);
 177                 let mut switch = ::cranelift::frontend::Switch::new();
 178                 for (i, value) in values.iter().enumerate() {
 179                     let ebb = fx.get_ebb(targets[i]);
 180                     switch.set_entry(*value as u64, ebb);
 181                 }
 182                 let otherwise_ebb = fx.get_ebb(targets[targets.len() - 1]);
 183                 switch.emit(&mut fx.bcx, discr, otherwise_ebb);
 184             }
 185             TerminatorKind::Call {
 186                 func,
 187                 args,
 188                 destination,
 189                 cleanup: _,
 190                 from_hir_call: _,
 191             } => {
 192                 crate::abi::codegen_terminator_call(fx, func, args, destination);
 193             }
 194             TerminatorKind::Resume | TerminatorKind::Abort => {
 195                 trap_unreachable(fx, "[corruption] Unwinding bb reached.");
 196             }
 197             TerminatorKind::Unreachable => {
 198                 trap_unreachable(fx, "[corruption] Hit unreachable code.");
 199             }
 200             TerminatorKind::Yield { .. }
 201             | TerminatorKind::FalseEdges { .. }
 202             | TerminatorKind::FalseUnwind { .. }
 203             | TerminatorKind::DropAndReplace { .. }
 204             | TerminatorKind::GeneratorDrop => {
 205                 bug!("shouldn't exist at trans {:?}", bb_data.terminator());
 206             }
 207             TerminatorKind::Drop {
 208                 location,
 209                 target,
 210                 unwind: _,
 211             } => {
 212                 let drop_place = trans_place(fx, location);
 213                 crate::abi::codegen_drop(fx, drop_place);
 214
 215                 let target_ebb = fx.get_ebb(*target);
 216                 fx.bcx.ins().jump(target_ebb, &[]);
 217             }
 218         };
 219     }
 220
 221     fx.bcx.seal_all_blocks();
 222     fx.bcx.finalize();
 223 }
 224
 225 fn trans_stmt<'a, 'tcx: 'a>(
 226     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 227     cur_ebb: Ebb,
 228     stmt: &Statement<'tcx>,
 229 ) {
 230     let _print_guard = PrintOnPanic(|| format!("stmt {:?}", stmt));
 231
 232     fx.set_debug_loc(stmt.source_info);
 233
 234     #[cfg(debug_assertions)]
 235     match &stmt.kind {
 236         StatementKind::StorageLive(..) | StatementKind::StorageDead(..) => {} // Those are not very useful
 237         _ => {
 238             let inst = fx.bcx.func.layout.last_inst(cur_ebb).unwrap();
 239             fx.add_comment(inst, format!("{:?}", stmt));
 240         }
 241     }
 242
 243     match &stmt.kind {
 244         StatementKind::SetDiscriminant {
 245             place,
 246             variant_index,
 247         } => {
 248             let place = trans_place(fx, place);
 249             let layout = place.layout();
 250             if layout.for_variant(&*fx, *variant_index).abi == layout::Abi::Uninhabited {
 251                 return;
 252             }
 253             match layout.variants {
 254                 layout::Variants::Single { index } => {
 255                     assert_eq!(index, *variant_index);
 256                 }
 257                 layout::Variants::Multiple {
 258                     discr: _,
 259                     discr_index,
 260                     discr_kind: layout::DiscriminantKind::Tag,
 261                     variants: _,
 262                 } => {
 263                     let ptr = place.place_field(fx, mir::Field::new(discr_index));
 264                     let to = layout
 265                         .ty
 266                         .discriminant_for_variant(fx.tcx, *variant_index)
 267                         .unwrap()
 268                         .val;
 269                     let discr = CValue::const_val(fx, ptr.layout().ty, to as u64 as i64);
 270                     ptr.write_cvalue(fx, discr);
 271                 }
 272                 layout::Variants::Multiple {
 273                     discr: _,
 274                     discr_index,
 275                     discr_kind: layout::DiscriminantKind::Niche {
 276                         dataful_variant,
 277                         ref niche_variants,
 278                         niche_start,
 279                     },
 280                     variants: _,
 281                 } => {
 282                     if *variant_index != dataful_variant {
 283                         let niche = place.place_field(fx, mir::Field::new(discr_index));
 284                         //let niche_llty = niche.layout.immediate_llvm_type(bx.cx);
 285                         let niche_value =
 286                             ((variant_index.as_u32() - niche_variants.start().as_u32()) as u128)
 287                                 .wrapping_add(niche_start);
 288                         // FIXME(eddyb) Check the actual primitive type here.
 289                         let niche_llval = if niche_value == 0 {
 290                             CValue::const_val(fx, niche.layout().ty, 0)
 291                         } else {
 292                             CValue::const_val(fx, niche.layout().ty, niche_value as u64 as i64)
 293                         };
 294                         niche.write_cvalue(fx, niche_llval);
 295                     }
 296                 }
 297             }
 298         }
 299         StatementKind::Assign(to_place, rval) => {
 300             let lval = trans_place(fx, to_place);
 301             let dest_layout = lval.layout();
 302             match &**rval {
 303                 Rvalue::Use(operand) => {
 304                     let val = trans_operand(fx, operand);
 305                     lval.write_cvalue(fx, val);
 306                 }
 307                 Rvalue::Ref(_, _, place) => {
 308                     let place = trans_place(fx, place);
 309                     place.write_place_ref(fx, lval);
 310                 }
 311                 Rvalue::BinaryOp(bin_op, lhs, rhs) => {
 312                     let ty = fx.monomorphize(&lhs.ty(fx.mir, fx.tcx));
 313                     let lhs = trans_operand(fx, lhs);
 314                     let rhs = trans_operand(fx, rhs);
 315
 316                     let res = match ty.sty {
 317                         ty::Bool => trans_bool_binop(fx, *bin_op, lhs, rhs),
 318                         ty::Uint(_) => {
 319                             trans_int_binop(fx, *bin_op, lhs, rhs, lval.layout().ty, false)
 320                         }
 321                         ty::Int(_) => {
 322                             trans_int_binop(fx, *bin_op, lhs, rhs, lval.layout().ty, true)
 323                         }
 324                         ty::Float(_) => trans_float_binop(fx, *bin_op, lhs, rhs, lval.layout().ty),
 325                         ty::Char => trans_char_binop(fx, *bin_op, lhs, rhs, lval.layout().ty),
 326                         ty::RawPtr(..) => trans_ptr_binop(fx, *bin_op, lhs, rhs, lval.layout().ty),
 327                         ty::FnPtr(..) => trans_ptr_binop(fx, *bin_op, lhs, rhs, lval.layout().ty),
 328                         _ => unimplemented!("binop {:?} for {:?}", bin_op, ty),
 329                     };
 330                     lval.write_cvalue(fx, res);
 331                 }
 332                 Rvalue::CheckedBinaryOp(bin_op, lhs, rhs) => {
 333                     let ty = fx.monomorphize(&lhs.ty(fx.mir, fx.tcx));
 334                     let lhs = trans_operand(fx, lhs);
 335                     let rhs = trans_operand(fx, rhs);
 336
 337                     let res = match ty.sty {
 338                         ty::Uint(_) => {
 339                             trans_checked_int_binop(fx, *bin_op, lhs, rhs, lval.layout().ty, false)
 340                         }
 341                         ty::Int(_) => {
 342                             trans_checked_int_binop(fx, *bin_op, lhs, rhs, lval.layout().ty, true)
 343                         }
 344                         _ => unimplemented!("checked binop {:?} for {:?}", bin_op, ty),
 345                     };
 346                     lval.write_cvalue(fx, res);
 347                 }
 348                 Rvalue::UnaryOp(un_op, operand) => {
 349                     let operand = trans_operand(fx, operand);
 350                     let layout = operand.layout();
 351                     let val = operand.load_scalar(fx);
 352                     let res = match un_op {
 353                         UnOp::Not => {
 354                             match layout.ty.sty {
 355                                 ty::Bool => {
 356                                     let val = fx.bcx.ins().uextend(types::I32, val); // WORKAROUND for CraneStation/cranelift#466
 357                                     let res = fx.bcx.ins().icmp_imm(IntCC::Equal, val, 0);
 358                                     fx.bcx.ins().bint(types::I8, res)
 359                                 }
 360                                 ty::Uint(_) | ty::Int(_) => {
 361                                     if fx.bcx.func.dfg.value_type(val) == types::I128 {
 362                                         let (a, b) = fx.bcx.ins().isplit(val);
 363                                         let a = fx.bcx.ins().bnot(a);
 364                                         let b = fx.bcx.ins().bnot(b);
 365                                         fx.bcx.ins().iconcat(a, b)
 366                                     } else {
 367                                         fx.bcx.ins().bnot(val)
 368                                     }
 369                                 }
 370                                 _ => unimplemented!("un op Not for {:?}", layout.ty),
 371                             }
 372                         }
 373                         UnOp::Neg => match layout.ty.sty {
 374                             ty::Int(_) => {
 375                                 let clif_ty = fx.clif_type(layout.ty).unwrap();
 376                                 if clif_ty == types::I128 {
 377                                     crate::trap::trap_unreachable_ret_value(fx, layout, "i128 neg is not yet supported").load_scalar(fx)
 378                                 } else {
 379                                     let zero = fx.bcx.ins().iconst(clif_ty, 0);
 380                                     fx.bcx.ins().isub(zero, val)
 381                                 }
 382                             }
 383                             ty::Float(_) => fx.bcx.ins().fneg(val),
 384                             _ => unimplemented!("un op Neg for {:?}", layout.ty),
 385                         },
 386                     };
 387                     lval.write_cvalue(fx, CValue::by_val(res, layout));
 388                 }
 389                 Rvalue::Cast(CastKind::Pointer(PointerCast::ReifyFnPointer), operand, ty) => {
 390                     let layout = fx.layout_of(ty);
 391                     match fx
 392                         .monomorphize(&operand.ty(&fx.mir.local_decls, fx.tcx))
 393                         .sty
 394                     {
 395                         ty::FnDef(def_id, substs) => {
 396                             let func_ref = fx.get_function_ref(
 397                                 Instance::resolve(fx.tcx, ParamEnv::reveal_all(), def_id, substs)
 398                                     .unwrap(),
 399                             );
 400                             let func_addr = fx.bcx.ins().func_addr(fx.pointer_type, func_ref);
 401                             lval.write_cvalue(fx, CValue::by_val(func_addr, layout));
 402                         }
 403                         _ => bug!("Trying to ReifyFnPointer on non FnDef {:?}", ty),
 404                     }
 405                 }
 406                 Rvalue::Cast(CastKind::Pointer(PointerCast::UnsafeFnPointer), operand, ty)
 407                 | Rvalue::Cast(CastKind::Pointer(PointerCast::MutToConstPointer), operand, ty) => {
 408                     let operand = trans_operand(fx, operand);
 409                     let layout = fx.layout_of(ty);
 410                     lval.write_cvalue(fx, operand.unchecked_cast_to(layout));
 411                 }
 412                 Rvalue::Cast(CastKind::Misc, operand, to_ty) => {
 413                     let operand = trans_operand(fx, operand);
 414                     let from_ty = operand.layout().ty;
 415
 416                     fn is_fat_ptr<'a, 'tcx: 'a>(fx: &FunctionCx<'a, 'tcx, impl Backend>, ty: Ty<'tcx>) -> bool {
 417                         ty
 418                             .builtin_deref(true)
 419                             .map(|ty::TypeAndMut {ty: pointee_ty, mutbl: _ }| fx.layout_of(pointee_ty).is_unsized())
 420                             .unwrap_or(false)
 421                     }
 422
 423                     if is_fat_ptr(fx, from_ty) {
 424                         if is_fat_ptr(fx, to_ty) {
 425                             // fat-ptr -> fat-ptr
 426                             lval.write_cvalue(fx, operand.unchecked_cast_to(dest_layout));
 427                         } else {
 428                             // fat-ptr -> thin-ptr
 429                             let (ptr, _extra) = operand.load_scalar_pair(fx);
 430                             lval.write_cvalue(fx, CValue::by_val(ptr, dest_layout))
 431                         }
 432                     } else if let ty::Adt(adt_def, _substs) = from_ty.sty {
 433                         // enum -> discriminant value
 434                         assert!(adt_def.is_enum());
 435                         match to_ty.sty {
 436                             ty::Uint(_) | ty::Int(_) => {},
 437                             _ => unreachable!("cast adt {} -> {}", from_ty, to_ty),
 438                         }
 439
 440                         // FIXME avoid forcing to stack
 441                         let place =
 442                             CPlace::for_addr(operand.force_stack(fx), operand.layout());
 443                         let discr = trans_get_discriminant(fx, place, fx.layout_of(to_ty));
 444                         lval.write_cvalue(fx, discr);
 445                     } else {
 446                         let from_clif_ty = fx.clif_type(from_ty).unwrap();
 447                         let to_clif_ty = fx.clif_type(to_ty).unwrap();
 448                         let from = operand.load_scalar(fx);
 449
 450                         let signed = match from_ty.sty {
 451                             ty::Ref(..) | ty::RawPtr(..) | ty::FnPtr(..) | ty::Char | ty::Uint(..) | ty::Bool => false,
 452                             ty::Int(..) => true,
 453                             ty::Float(..) => false, // `signed` is unused for floats
 454                             _ => panic!("{}", from_ty),
 455                         };
 456
 457                         let res = if from_clif_ty.is_int() && to_clif_ty.is_int() {
 458                             // int-like -> int-like
 459                             crate::common::clif_intcast(
 460                                 fx,
 461                                 from,
 462                                 to_clif_ty,
 463                                 signed,
 464                             )
 465                         } else if from_clif_ty.is_int() && to_clif_ty.is_float() {
 466                             // int-like -> float
 467                             if signed {
 468                                 fx.bcx.ins().fcvt_from_sint(to_clif_ty, from)
 469                             } else {
 470                                 fx.bcx.ins().fcvt_from_uint(to_clif_ty, from)
 471                             }
 472                         } else if from_clif_ty.is_float() && to_clif_ty.is_int() {
 473                             // float -> int-like
 474                             let from = operand.load_scalar(fx);
 475                             if signed {
 476                                 fx.bcx.ins().fcvt_to_sint_sat(to_clif_ty, from)
 477                             } else {
 478                                 fx.bcx.ins().fcvt_to_uint_sat(to_clif_ty, from)
 479                             }
 480                         } else if from_clif_ty.is_float() && to_clif_ty.is_float() {
 481                             // float -> float
 482                             match (from_clif_ty, to_clif_ty) {
 483                                 (types::F32, types::F64) => {
 484                                     fx.bcx.ins().fpromote(types::F64, from)
 485                                 }
 486                                 (types::F64, types::F32) => {
 487                                     fx.bcx.ins().fdemote(types::F32, from)
 488                                 }
 489                                 _ => from,
 490                             }
 491                         } else {
 492                             unimpl!("rval misc {:?} {:?}", from_ty, to_ty)
 493                         };
 494                         lval.write_cvalue(fx, CValue::by_val(res, dest_layout));
 495                     }
 496                 }
 497                 Rvalue::Cast(CastKind::Pointer(PointerCast::ClosureFnPointer(_)), operand, _ty) => {
 498                     let operand = trans_operand(fx, operand);
 499                     match operand.layout().ty.sty {
 500                         ty::Closure(def_id, substs) => {
 501                             let instance = Instance::resolve_closure(
 502                                 fx.tcx,
 503                                 def_id,
 504                                 substs,
 505                                 ty::ClosureKind::FnOnce,
 506                             );
 507                             let func_ref = fx.get_function_ref(instance);
 508                             let func_addr = fx.bcx.ins().func_addr(fx.pointer_type, func_ref);
 509                             lval.write_cvalue(fx, CValue::by_val(func_addr, lval.layout()));
 510                         }
 511                         _ => {
 512                             bug!("{} cannot be cast to a fn ptr", operand.layout().ty)
 513                         }
 514                     }
 515                 }
 516                 Rvalue::Cast(CastKind::Pointer(PointerCast::Unsize), operand, _ty) => {
 517                     let operand = trans_operand(fx, operand);
 518                     operand.unsize_value(fx, lval);
 519                 }
 520                 Rvalue::Discriminant(place) => {
 521                     let place = trans_place(fx, place);
 522                     let discr = trans_get_discriminant(fx, place, dest_layout);
 523                     lval.write_cvalue(fx, discr);
 524                 }
 525                 Rvalue::Repeat(operand, times) => {
 526                     let operand = trans_operand(fx, operand);
 527                     for i in 0..*times {
 528                         let index = fx.bcx.ins().iconst(fx.pointer_type, i as i64);
 529                         let to = lval.place_index(fx, index);
 530                         to.write_cvalue(fx, operand);
 531                     }
 532                 }
 533                 Rvalue::Len(place) => {
 534                     let place = trans_place(fx, place);
 535                     let usize_layout = fx.layout_of(fx.tcx.types.usize);
 536                     let len = codegen_array_len(fx, place);
 537                     lval.write_cvalue(fx, CValue::by_val(len, usize_layout));
 538                 }
 539                 Rvalue::NullaryOp(NullOp::Box, content_ty) => {
 540                     use rustc::middle::lang_items::ExchangeMallocFnLangItem;
 541
 542                     let usize_type = fx.clif_type(fx.tcx.types.usize).unwrap();
 543                     let layout = fx.layout_of(content_ty);
 544                     let llsize = fx.bcx.ins().iconst(usize_type, layout.size.bytes() as i64);
 545                     let llalign = fx
 546                         .bcx
 547                         .ins()
 548                         .iconst(usize_type, layout.align.abi.bytes() as i64);
 549                     let box_layout = fx.layout_of(fx.tcx.mk_box(content_ty));
 550
 551                     // Allocate space:
 552                     let def_id = match fx.tcx.lang_items().require(ExchangeMallocFnLangItem) {
 553                         Ok(id) => id,
 554                         Err(s) => {
 555                             fx.tcx
 556                                 .sess
 557                                 .fatal(&format!("allocation of `{}` {}", box_layout.ty, s));
 558                         }
 559                     };
 560                     let instance = ty::Instance::mono(fx.tcx, def_id);
 561                     let func_ref = fx.get_function_ref(instance);
 562                     let call = fx.bcx.ins().call(func_ref, &[llsize, llalign]);
 563                     let ptr = fx.bcx.inst_results(call)[0];
 564                     lval.write_cvalue(fx, CValue::by_val(ptr, box_layout));
 565                 }
 566                 Rvalue::NullaryOp(NullOp::SizeOf, ty) => {
 567                     assert!(lval
 568                         .layout()
 569                         .ty
 570                         .is_sized(fx.tcx.at(DUMMY_SP), ParamEnv::reveal_all()));
 571                     let ty_size = fx.layout_of(ty).size.bytes();
 572                     let val = CValue::const_val(fx, fx.tcx.types.usize, ty_size as i64);
 573                     lval.write_cvalue(fx, val);
 574                 }
 575                 Rvalue::Aggregate(kind, operands) => match **kind {
 576                     AggregateKind::Array(_ty) => {
 577                         for (i, operand) in operands.into_iter().enumerate() {
 578                             let operand = trans_operand(fx, operand);
 579                             let index = fx.bcx.ins().iconst(fx.pointer_type, i as i64);
 580                             let to = lval.place_index(fx, index);
 581                             to.write_cvalue(fx, operand);
 582                         }
 583                     }
 584                     _ => unimpl!("shouldn't exist at trans {:?}", rval),
 585                 },
 586             }
 587         }
 588         StatementKind::StorageLive(_)
 589         | StatementKind::StorageDead(_)
 590         | StatementKind::Nop
 591         | StatementKind::FakeRead(..)
 592         | StatementKind::Retag { .. }
 593         | StatementKind::AscribeUserType(..) => {}
 594
 595         StatementKind::InlineAsm(asm) => {
 596             use syntax::ast::Name;
 597             let InlineAsm { asm, outputs: _, inputs: _ } = &**asm;
 598             let rustc::hir::InlineAsm {
 599                 asm: asm_code, // Name
 600                 outputs, // Vec<Name>
 601                 inputs, // Vec<Name>
 602                 clobbers, // Vec<Name>
 603                 volatile, // bool
 604                 alignstack, // bool
 605                 dialect: _, // syntax::ast::AsmDialect
 606                 asm_str_style: _,
 607                 ctxt: _,
 608             } = asm;
 609             match &*asm_code.as_str() {
 610                 "cpuid" | "cpuid\n" => {
 611                     assert_eq!(inputs, &[Name::intern("{eax}"), Name::intern("{ecx}")]);
 612
 613                     assert_eq!(outputs.len(), 4);
 614                     for (i, c) in (&["={eax}", "={ebx}", "={ecx}", "={edx}"]).iter().enumerate() {
 615                         assert_eq!(&outputs[i].constraint.as_str(), c);
 616                         assert!(!outputs[i].is_rw);
 617                         assert!(!outputs[i].is_indirect);
 618                     }
 619
 620                     assert_eq!(clobbers, &[Name::intern("rbx")]);
 621
 622                     assert!(!volatile);
 623                     assert!(!alignstack);
 624
 625                     crate::trap::trap_unimplemented(fx, "__cpuid_count arch intrinsic is not supported");
 626                 }
 627                 "xgetbv" => {
 628                     assert_eq!(inputs, &[Name::intern("{ecx}")]);
 629
 630                     assert_eq!(outputs.len(), 2);
 631                     for (i, c) in (&["={eax}", "={edx}"]).iter().enumerate() {
 632                         assert_eq!(&outputs[i].constraint.as_str(), c);
 633                         assert!(!outputs[i].is_rw);
 634                         assert!(!outputs[i].is_indirect);
 635                     }
 636
 637                     assert_eq!(clobbers, &[]);
 638
 639                     assert!(!volatile);
 640                     assert!(!alignstack);
 641
 642                     crate::trap::trap_unimplemented(fx, "_xgetbv arch intrinsic is not supported");
 643                 }
 644                 _ if fx.tcx.symbol_name(fx.instance).as_str() == "__rust_probestack" => {
 645                     crate::trap::trap_unimplemented(fx, "__rust_probestack is not supported");
 646                 }
 647                 _ => unimpl!("Inline assembly is not supported"),
 648             }
 649         }
 650     }
 651 }
 652
 653 fn codegen_array_len<'a, 'tcx: 'a>(
 654     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 655     place: CPlace<'tcx>,
 656 ) -> Value {
 657     match place.layout().ty.sty {
 658         ty::Array(_elem_ty, len) => {
 659             let len = crate::constant::force_eval_const(fx, len).unwrap_usize(fx.tcx) as i64;
 660             fx.bcx.ins().iconst(fx.pointer_type, len)
 661         }
 662         ty::Slice(_elem_ty) => place
 663             .to_addr_maybe_unsized(fx)
 664             .1
 665             .expect("Length metadata for slice place"),
 666         _ => bug!("Rvalue::Len({:?})", place),
 667     }
 668 }
 669
 670 pub fn trans_get_discriminant<'a, 'tcx: 'a>(
 671     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 672     place: CPlace<'tcx>,
 673     dest_layout: TyLayout<'tcx>,
 674 ) -> CValue<'tcx> {
 675     let layout = place.layout();
 676
 677     if layout.abi == layout::Abi::Uninhabited {
 678         return trap_unreachable_ret_value(fx, dest_layout, "[panic] Tried to get discriminant for uninhabited type.");
 679     }
 680
 681     let (discr_scalar, discr_index, discr_kind) = match &layout.variants {
 682         layout::Variants::Single { index } => {
 683             let discr_val = layout
 684                 .ty
 685                 .ty_adt_def()
 686                 .map_or(index.as_u32() as u128, |def| {
 687                     def.discriminant_for_variant(fx.tcx, *index).val
 688                 });
 689             return CValue::const_val(fx, dest_layout.ty, discr_val as u64 as i64);
 690         }
 691         layout::Variants::Multiple { discr, discr_index, discr_kind, variants: _ } => {
 692             (discr, *discr_index, discr_kind)
 693         }
 694     };
 695
 696     let discr = place.place_field(fx, mir::Field::new(discr_index)).to_cvalue(fx);
 697     let discr_ty = discr.layout().ty;
 698     let lldiscr = discr.load_scalar(fx);
 699     match discr_kind {
 700         layout::DiscriminantKind::Tag => {
 701             let signed = match discr_scalar.value {
 702                 layout::Int(_, signed) => signed,
 703                 _ => false,
 704             };
 705             let val = clif_intcast(fx, lldiscr, fx.clif_type(dest_layout.ty).unwrap(), signed);
 706             return CValue::by_val(val, dest_layout);
 707         }
 708         layout::DiscriminantKind::Niche {
 709             dataful_variant,
 710             ref niche_variants,
 711             niche_start,
 712         } => {
 713             let niche_llty = fx.clif_type(discr_ty).unwrap();
 714             let dest_clif_ty = fx.clif_type(dest_layout.ty).unwrap();
 715             if niche_variants.start() == niche_variants.end() {
 716                 let b = fx
 717                     .bcx
 718                     .ins()
 719                     .icmp_imm(IntCC::Equal, lldiscr, *niche_start as u64 as i64);
 720                 let if_true = fx
 721                     .bcx
 722                     .ins()
 723                     .iconst(dest_clif_ty, niche_variants.start().as_u32() as i64);
 724                 let if_false = fx
 725                     .bcx
 726                     .ins()
 727                     .iconst(dest_clif_ty, dataful_variant.as_u32() as i64);
 728                 let val = fx.bcx.ins().select(b, if_true, if_false);
 729                 return CValue::by_val(val, dest_layout);
 730             } else {
 731                 // Rebase from niche values to discriminant values.
 732                 let delta = niche_start.wrapping_sub(niche_variants.start().as_u32() as u128);
 733                 let delta = fx.bcx.ins().iconst(niche_llty, delta as u64 as i64);
 734                 let lldiscr = fx.bcx.ins().isub(lldiscr, delta);
 735                 let b = fx.bcx.ins().icmp_imm(
 736                     IntCC::UnsignedLessThanOrEqual,
 737                     lldiscr,
 738                     niche_variants.end().as_u32() as i64,
 739                 );
 740                 let if_true =
 741                     clif_intcast(fx, lldiscr, fx.clif_type(dest_layout.ty).unwrap(), false);
 742                 let if_false = fx
 743                     .bcx
 744                     .ins()
 745                     .iconst(dest_clif_ty, dataful_variant.as_u32() as i64);
 746                 let val = fx.bcx.ins().select(b, if_true, if_false);
 747                 return CValue::by_val(val, dest_layout);
 748             }
 749         }
 750     }
 751 }
 752
 753 macro_rules! binop_match {
 754     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, bug) => {
 755         bug!("binop {} on {} lhs: {:?} rhs: {:?}", stringify!($var), $bug_fmt, $lhs, $rhs)
 756     };
 757     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, icmp($cc:ident)) => {{
 758         assert_eq!($fx.tcx.types.bool, $ret_ty);
 759         let ret_layout = $fx.layout_of($ret_ty);
 760
 761         let b = $fx.bcx.ins().icmp(IntCC::$cc, $lhs, $rhs);
 762         CValue::by_val($fx.bcx.ins().bint(types::I8, b), ret_layout)
 763     }};
 764     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, fcmp($cc:ident)) => {{
 765         assert_eq!($fx.tcx.types.bool, $ret_ty);
 766         let ret_layout = $fx.layout_of($ret_ty);
 767         let b = $fx.bcx.ins().fcmp(FloatCC::$cc, $lhs, $rhs);
 768         CValue::by_val($fx.bcx.ins().bint(types::I8, b), ret_layout)
 769     }};
 770     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, custom(|| $body:expr)) => {{
 771         $body
 772     }};
 773     (@single $fx:expr, $bug_fmt:expr, $var:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, $name:ident) => {{
 774         let ret_layout = $fx.layout_of($ret_ty);
 775         CValue::by_val($fx.bcx.ins().$name($lhs, $rhs), ret_layout)
 776     }};
 777     (
 778         $fx:expr, $bin_op:expr, $signed:expr, $lhs:expr, $rhs:expr, $ret_ty:expr, $bug_fmt:expr;
 779         $(
 780             $var:ident ($sign:pat) $name:tt $( ( $($next:tt)* ) )? ;
 781         )*
 782     ) => {{
 783         let lhs = $lhs.load_scalar($fx);
 784         let rhs = $rhs.load_scalar($fx);
 785         match ($bin_op, $signed) {
 786             $(
 787                 (BinOp::$var, $sign) => binop_match!(@single $fx, $bug_fmt, $var, $signed, lhs, rhs, $ret_ty, $name $( ( $($next)* ) )?),
 788             )*
 789         }
 790     }}
 791 }
 792
 793 fn trans_bool_binop<'a, 'tcx: 'a>(
 794     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 795     bin_op: BinOp,
 796     lhs: CValue<'tcx>,
 797     rhs: CValue<'tcx>,
 798 ) -> CValue<'tcx> {
 799     let res = binop_match! {
 800         fx, bin_op, false, lhs, rhs, fx.tcx.types.bool, "bool";
 801         Add (_) bug;
 802         Sub (_) bug;
 803         Mul (_) bug;
 804         Div (_) bug;
 805         Rem (_) bug;
 806         BitXor (_) bxor;
 807         BitAnd (_) band;
 808         BitOr (_) bor;
 809         Shl (_) bug;
 810         Shr (_) bug;
 811
 812         Eq (_) icmp(Equal);
 813         Lt (_) icmp(UnsignedLessThan);
 814         Le (_) icmp(UnsignedLessThanOrEqual);
 815         Ne (_) icmp(NotEqual);
 816         Ge (_) icmp(UnsignedGreaterThanOrEqual);
 817         Gt (_) icmp(UnsignedGreaterThan);
 818
 819         Offset (_) bug;
 820     };
 821
 822     res
 823 }
 824
 825 pub fn trans_int_binop<'a, 'tcx: 'a>(
 826     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 827     bin_op: BinOp,
 828     lhs: CValue<'tcx>,
 829     rhs: CValue<'tcx>,
 830     out_ty: Ty<'tcx>,
 831     signed: bool,
 832 ) -> CValue<'tcx> {
 833     if bin_op != BinOp::Shl && bin_op != BinOp::Shr {
 834         assert_eq!(
 835             lhs.layout().ty,
 836             rhs.layout().ty,
 837             "int binop requires lhs and rhs of same type"
 838         );
 839     }
 840
 841     if lhs.layout().ty == fx.tcx.types.u128 || lhs.layout().ty == fx.tcx.types.i128 {
 842         if out_ty == fx.tcx.types.bool {
 843             let layout = fx.layout_of(fx.tcx.types.bool);
 844             let val = fx.bcx.ins().iconst(types::I8, 0);
 845             return CValue::by_val(val, layout);
 846         } else {
 847             let layout = fx.layout_of(out_ty);
 848             let a = fx.bcx.ins().iconst(types::I64, 42);
 849             let b = fx.bcx.ins().iconst(types::I64, 0);
 850             let val = fx.bcx.ins().iconcat(a, b);
 851             return CValue::by_val(val, layout);
 852         }
 853     }
 854
 855     binop_match! {
 856         fx, bin_op, signed, lhs, rhs, out_ty, "int/uint";
 857         Add (_) iadd;
 858         Sub (_) isub;
 859         Mul (_) imul;
 860         Div (false) udiv;
 861         Div (true) sdiv;
 862         Rem (false) urem;
 863         Rem (true) srem;
 864         BitXor (_) bxor;
 865         BitAnd (_) band;
 866         BitOr (_) bor;
 867         Shl (_) ishl;
 868         Shr (false) ushr;
 869         Shr (true) sshr;
 870
 871         Eq (_) icmp(Equal);
 872         Lt (false) icmp(UnsignedLessThan);
 873         Lt (true) icmp(SignedLessThan);
 874         Le (false) icmp(UnsignedLessThanOrEqual);
 875         Le (true) icmp(SignedLessThanOrEqual);
 876         Ne (_) icmp(NotEqual);
 877         Ge (false) icmp(UnsignedGreaterThanOrEqual);
 878         Ge (true) icmp(SignedGreaterThanOrEqual);
 879         Gt (false) icmp(UnsignedGreaterThan);
 880         Gt (true) icmp(SignedGreaterThan);
 881
 882         Offset (_) bug;
 883     }
 884 }
 885
 886 pub fn trans_checked_int_binop<'a, 'tcx: 'a>(
 887     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 888     bin_op: BinOp,
 889     in_lhs: CValue<'tcx>,
 890     in_rhs: CValue<'tcx>,
 891     out_ty: Ty<'tcx>,
 892     signed: bool,
 893 ) -> CValue<'tcx> {
 894     if bin_op != BinOp::Shl && bin_op != BinOp::Shr {
 895         assert_eq!(
 896             in_lhs.layout().ty,
 897             in_rhs.layout().ty,
 898             "checked int binop requires lhs and rhs of same type"
 899         );
 900     }
 901
 902     let lhs = in_lhs.load_scalar(fx);
 903     let rhs = in_rhs.load_scalar(fx);
 904     let (res, has_overflow) = if in_lhs.layout().ty == fx.tcx.types.u128 || in_lhs.layout().ty == fx.tcx.types.i128 {
 905         match (bin_op, signed) {
 906             _ => {
 907                 let a = fx.bcx.ins().iconst(types::I64, 42);
 908                 let b = fx.bcx.ins().iconst(types::I64, 0);
 909                 (fx.bcx.ins().iconcat(a, b), fx.bcx.ins().bconst(types::B1, false))
 910             }
 911         }
 912     } else {
 913         match bin_op {
 914             BinOp::Add => {
 915                 /*let (val, c_out) = fx.bcx.ins().iadd_cout(lhs, rhs);
 916                 (val, c_out)*/
 917                 // FIXME(CraneStation/cranelift#849) legalize iadd_cout for i8 and i16
 918                 let val = fx.bcx.ins().iadd(lhs, rhs);
 919                 let has_overflow = if !signed {
 920                     fx.bcx.ins().icmp(IntCC::UnsignedLessThan, val, lhs)
 921                 } else {
 922                     let rhs_is_negative = fx.bcx.ins().icmp_imm(IntCC::SignedLessThan, rhs, 0);
 923                     let slt = fx.bcx.ins().icmp(IntCC::SignedLessThan, val, lhs);
 924                     fx.bcx.ins().bxor(rhs_is_negative, slt)
 925                 };
 926                 (val, has_overflow)
 927             }
 928             BinOp::Sub => {
 929                 /*let (val, b_out) = fx.bcx.ins().isub_bout(lhs, rhs);
 930                 (val, b_out)*/
 931                 // FIXME(CraneStation/cranelift#849) legalize isub_bout for i8 and i16
 932                 let val = fx.bcx.ins().isub(lhs, rhs);
 933                 let has_overflow = if !signed {
 934                     fx.bcx.ins().icmp(IntCC::UnsignedGreaterThan, val, lhs)
 935                 } else {
 936                     let rhs_is_negative = fx.bcx.ins().icmp_imm(IntCC::SignedLessThan, rhs, 0);
 937                     let sgt = fx.bcx.ins().icmp(IntCC::SignedGreaterThan, val, lhs);
 938                     fx.bcx.ins().bxor(rhs_is_negative, sgt)
 939                 };
 940                 (val, has_overflow)
 941             }
 942             BinOp::Mul => {
 943                 let val = fx.bcx.ins().imul(lhs, rhs);
 944                 /*let val_hi = if !signed {
 945                     fx.bcx.ins().umulhi(lhs, rhs)
 946                 } else {
 947                     fx.bcx.ins().smulhi(lhs, rhs)
 948                 };
 949                 let has_overflow = fx.bcx.ins().icmp_imm(IntCC::NotEqual, val_hi, 0);*/
 950                 // TODO: check for overflow
 951                 let has_overflow = fx.bcx.ins().bconst(types::B1, false);
 952                 (val, has_overflow)
 953             }
 954             BinOp::Shl => {
 955                 let val = fx.bcx.ins().ishl(lhs, rhs);
 956                 // TODO: check for overflow
 957                 let has_overflow = fx.bcx.ins().bconst(types::B1, false);
 958                 (val, has_overflow)
 959             }
 960             BinOp::Shr => {
 961                 let val = if !signed {
 962                     fx.bcx.ins().ushr(lhs, rhs)
 963                 } else {
 964                     fx.bcx.ins().sshr(lhs, rhs)
 965                 };
 966                 // TODO: check for overflow
 967                 let has_overflow = fx.bcx.ins().bconst(types::B1, false);
 968                 (val, has_overflow)
 969             }
 970             _ => bug!(
 971                 "binop {:?} on checked int/uint lhs: {:?} rhs: {:?}",
 972                 bin_op,
 973                 in_lhs,
 974                 in_rhs
 975             ),
 976         }
 977     };
 978
 979     let has_overflow = fx.bcx.ins().bint(types::I8, has_overflow);
 980     let out_place = CPlace::new_stack_slot(fx, out_ty);
 981     let out_layout = out_place.layout();
 982     out_place.write_cvalue(fx, CValue::by_val_pair(res, has_overflow, out_layout));
 983
 984     out_place.to_cvalue(fx)
 985 }
 986
 987 fn trans_float_binop<'a, 'tcx: 'a>(
 988     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
 989     bin_op: BinOp,
 990     lhs: CValue<'tcx>,
 991     rhs: CValue<'tcx>,
 992     ty: Ty<'tcx>,
 993 ) -> CValue<'tcx> {
 994     let res = binop_match! {
 995         fx, bin_op, false, lhs, rhs, ty, "float";
 996         Add (_) fadd;
 997         Sub (_) fsub;
 998         Mul (_) fmul;
 999         Div (_) fdiv;
1000         Rem (_) custom(|| {
1001             assert_eq!(lhs.layout().ty, ty);
1002             assert_eq!(rhs.layout().ty, ty);
1003             match ty.sty {
1004                 ty::Float(FloatTy::F32) => fx.easy_call("fmodf", &[lhs, rhs], ty),
1005                 ty::Float(FloatTy::F64) => fx.easy_call("fmod", &[lhs, rhs], ty),
1006                 _ => bug!(),
1007             }
1008         });
1009         BitXor (_) bxor;
1010         BitAnd (_) band;
1011         BitOr (_) bor;
1012         Shl (_) bug;
1013         Shr (_) bug;
1014
1015         Eq (_) fcmp(Equal);
1016         Lt (_) fcmp(LessThan);
1017         Le (_) fcmp(LessThanOrEqual);
1018         Ne (_) fcmp(NotEqual);
1019         Ge (_) fcmp(GreaterThanOrEqual);
1020         Gt (_) fcmp(GreaterThan);
1021
1022         Offset (_) bug;
1023     };
1024
1025     res
1026 }
1027
1028 fn trans_char_binop<'a, 'tcx: 'a>(
1029     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
1030     bin_op: BinOp,
1031     lhs: CValue<'tcx>,
1032     rhs: CValue<'tcx>,
1033     ty: Ty<'tcx>,
1034 ) -> CValue<'tcx> {
1035     let res = binop_match! {
1036         fx, bin_op, false, lhs, rhs, ty, "char";
1037         Add (_) bug;
1038         Sub (_) bug;
1039         Mul (_) bug;
1040         Div (_) bug;
1041         Rem (_) bug;
1042         BitXor (_) bug;
1043         BitAnd (_) bug;
1044         BitOr (_) bug;
1045         Shl (_) bug;
1046         Shr (_) bug;
1047
1048         Eq (_) icmp(Equal);
1049         Lt (_) icmp(UnsignedLessThan);
1050         Le (_) icmp(UnsignedLessThanOrEqual);
1051         Ne (_) icmp(NotEqual);
1052         Ge (_) icmp(UnsignedGreaterThanOrEqual);
1053         Gt (_) icmp(UnsignedGreaterThan);
1054
1055         Offset (_) bug;
1056     };
1057
1058     res
1059 }
1060
1061 fn trans_ptr_binop<'a, 'tcx: 'a>(
1062     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
1063     bin_op: BinOp,
1064     lhs: CValue<'tcx>,
1065     rhs: CValue<'tcx>,
1066     ret_ty: Ty<'tcx>,
1067 ) -> CValue<'tcx> {
1068     let not_fat = match lhs.layout().ty.sty {
1069         ty::RawPtr(TypeAndMut { ty, mutbl: _ }) => {
1070             ty.is_sized(fx.tcx.at(DUMMY_SP), ParamEnv::reveal_all())
1071         }
1072         ty::FnPtr(..) => true,
1073         _ => bug!("trans_ptr_binop on non ptr"),
1074     };
1075     if not_fat {
1076         if let BinOp::Offset = bin_op {
1077             let (base, offset) = (lhs, rhs.load_scalar(fx));
1078             let pointee_ty = base.layout().ty.builtin_deref(true).unwrap().ty;
1079             let pointee_size = fx.layout_of(pointee_ty).size.bytes();
1080             let ptr_diff = fx.bcx.ins().imul_imm(offset, pointee_size as i64);
1081             let base_val = base.load_scalar(fx);
1082             let res = fx.bcx.ins().iadd(base_val, ptr_diff);
1083             return CValue::by_val(res, base.layout());
1084         }
1085
1086         binop_match! {
1087             fx, bin_op, false, lhs, rhs, ret_ty, "ptr";
1088             Add (_) bug;
1089             Sub (_) bug;
1090             Mul (_) bug;
1091             Div (_) bug;
1092             Rem (_) bug;
1093             BitXor (_) bug;
1094             BitAnd (_) bug;
1095             BitOr (_) bug;
1096             Shl (_) bug;
1097             Shr (_) bug;
1098
1099             Eq (_) icmp(Equal);
1100             Lt (_) icmp(UnsignedLessThan);
1101             Le (_) icmp(UnsignedLessThanOrEqual);
1102             Ne (_) icmp(NotEqual);
1103             Ge (_) icmp(UnsignedGreaterThanOrEqual);
1104             Gt (_) icmp(UnsignedGreaterThan);
1105
1106             Offset (_) bug; // Handled above
1107         }
1108     } else {
1109         let (lhs_ptr, lhs_extra) = lhs.load_scalar_pair(fx);
1110         let (rhs_ptr, rhs_extra) = rhs.load_scalar_pair(fx);
1111
1112         let res = match bin_op {
1113             BinOp::Eq => {
1114                 let ptr_eq = fx.bcx.ins().icmp(IntCC::Equal, lhs_ptr, rhs_ptr);
1115                 let extra_eq = fx.bcx.ins().icmp(IntCC::Equal, lhs_extra, rhs_extra);
1116                 fx.bcx.ins().band(ptr_eq, extra_eq)
1117             }
1118             BinOp::Ne => {
1119                 let ptr_ne = fx.bcx.ins().icmp(IntCC::NotEqual, lhs_ptr, rhs_ptr);
1120                 let extra_ne = fx.bcx.ins().icmp(IntCC::NotEqual, lhs_extra, rhs_extra);
1121                 fx.bcx.ins().bor(ptr_ne, extra_ne)
1122             }
1123             BinOp::Lt | BinOp::Le | BinOp::Ge | BinOp::Gt => {
1124                 let ptr_eq = fx.bcx.ins().icmp(IntCC::Equal, lhs_ptr, rhs_ptr);
1125
1126                 let ptr_cmp = fx.bcx.ins().icmp(match bin_op {
1127                     BinOp::Lt => IntCC::UnsignedLessThan,
1128                     BinOp::Le => IntCC::UnsignedLessThanOrEqual,
1129                     BinOp::Ge => IntCC::UnsignedGreaterThanOrEqual,
1130                     BinOp::Gt => IntCC::UnsignedGreaterThan,
1131                     _ => unreachable!(),
1132                 }, lhs_ptr, rhs_ptr);
1133
1134                 let extra_cmp = fx.bcx.ins().icmp(match bin_op {
1135                     BinOp::Lt => IntCC::UnsignedLessThan,
1136                     BinOp::Le => IntCC::UnsignedLessThanOrEqual,
1137                     BinOp::Ge => IntCC::UnsignedGreaterThanOrEqual,
1138                     BinOp::Gt => IntCC::UnsignedGreaterThan,
1139                     _ => unreachable!(),
1140                 }, lhs_extra, rhs_extra);
1141
1142                 fx.bcx.ins().select(ptr_eq, extra_cmp, ptr_cmp)
1143             }
1144             _ => panic!("bin_op {:?} on ptr", bin_op),
1145         };
1146
1147         assert_eq!(fx.tcx.types.bool, ret_ty);
1148         let ret_layout = fx.layout_of(ret_ty);
1149         CValue::by_val(fx.bcx.ins().bint(types::I8, res), ret_layout)
1150     }
1151 }
1152
1153 pub fn trans_place<'a, 'tcx: 'a>(
1154     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
1155     place: &Place<'tcx>,
1156 ) -> CPlace<'tcx> {
1157     let base = match &place.base {
1158         PlaceBase::Local(local) => fx.get_local_place(*local),
1159         PlaceBase::Static(static_) => match static_.kind {
1160             StaticKind::Static(def_id) => {
1161                 crate::constant::codegen_static_ref(fx, def_id, static_.ty)
1162             }
1163             StaticKind::Promoted(promoted) => {
1164                 crate::constant::trans_promoted(fx, promoted, static_.ty)
1165             }
1166         }
1167     };
1168
1169     trans_place_projection(fx, base, &place.projection)
1170 }
1171
1172 pub fn trans_place_projection<'a, 'tcx: 'a>(
1173     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
1174     base: CPlace<'tcx>,
1175     projection: &Option<Box<Projection<'tcx>>>,
1176 ) -> CPlace<'tcx> {
1177     let projection = if let Some(projection) = projection {
1178         projection
1179     } else {
1180         return base;
1181     };
1182
1183     let base = trans_place_projection(fx, base, &projection.base);
1184
1185     match projection.elem {
1186         ProjectionElem::Deref => base.place_deref(fx),
1187         ProjectionElem::Field(field, _ty) => base.place_field(fx, field),
1188         ProjectionElem::Index(local) => {
1189             let index = fx.get_local_place(local).to_cvalue(fx).load_scalar(fx);
1190             base.place_index(fx, index)
1191         }
1192         ProjectionElem::ConstantIndex {
1193             offset,
1194             min_length: _,
1195             from_end,
1196         } => {
1197             let index = if !from_end {
1198                 fx.bcx.ins().iconst(fx.pointer_type, offset as i64)
1199             } else {
1200                 let len = codegen_array_len(fx, base);
1201                 fx.bcx.ins().iadd_imm(len, -(offset as i64))
1202             };
1203             base.place_index(fx, index)
1204         }
1205         ProjectionElem::Subslice { from, to } => {
1206             // These indices are generated by slice patterns.
1207             // slice[from:-to] in Python terms.
1208
1209             match base.layout().ty.sty {
1210                 ty::Array(elem_ty, len) => {
1211                     let elem_layout = fx.layout_of(elem_ty);
1212                     let ptr = base.to_addr(fx);
1213                     let len = crate::constant::force_eval_const(fx, len).unwrap_usize(fx.tcx);
1214                     CPlace::for_addr(
1215                         fx.bcx.ins().iadd_imm(ptr, elem_layout.size.bytes() as i64 * from as i64),
1216                         fx.layout_of(fx.tcx.mk_array(elem_ty, len - from as u64 - to as u64)),
1217                     )
1218                 }
1219                 ty::Slice(elem_ty) => {
1220                     let elem_layout = fx.layout_of(elem_ty);
1221                     let (ptr, len) = base.to_addr_maybe_unsized(fx);
1222                     let len = len.unwrap();
1223                     CPlace::for_addr_with_extra(
1224                         fx.bcx.ins().iadd_imm(ptr, elem_layout.size.bytes() as i64 * from as i64),
1225                         fx.bcx.ins().iadd_imm(len, -(from as i64 + to as i64)),
1226                         base.layout(),
1227                     )
1228                 }
1229                 _ => unreachable!(),
1230             }
1231         }
1232         ProjectionElem::Downcast(_adt_def, variant) => base.downcast_variant(fx, variant),
1233     }
1234 }
1235
1236 pub fn trans_operand<'a, 'tcx>(
1237     fx: &mut FunctionCx<'a, 'tcx, impl Backend>,
1238     operand: &Operand<'tcx>,
1239 ) -> CValue<'tcx> {
1240     match operand {
1241         Operand::Move(place) | Operand::Copy(place) => {
1242             let cplace = trans_place(fx, place);
1243             cplace.to_cvalue(fx)
1244         }
1245         Operand::Constant(const_) => crate::constant::trans_constant(fx, const_),
1246     }
1247 }